DE202005004971U1 - Molten metal rotary drum furnace has two-part stirrer body on drum whose parts are detachably connected together for easier replacement - Google Patents

Abstract

The furnace has a stirrer body (3) on the drum sleeve (2). The stirrer is in two parts (3a,3b) which can be detachably connected together. The stirrer body is preferably divided crosswise. Both parts adjoin one another on a common partition plane whose distance from the drum sleeve matches the thickness of the inner lining (5) of the furnace drum (1).

Description

The The invention relates to a molten metal rotary drum furnace, in particular for remelting aluminum, preferably in a protective bath, with a rotatable kiln drum whose drum shell at least has a stirring body projecting into the interior of the furnace drum.

Such molten metal rotary furnaces are known in various designs. Reference is made only by way of example to the utility model DE 203 03 289 U1 or even the US 6,395,221 B1 ,

The known metal melt rotary drum ovens have proven to be however, capable of improvement, what the assembly of the stirring body and their Installation and removal As. Indeed have such Metal melting rotary drum ovens over one Inner lining of, for example, refractory material such as firebricks, in which the stirring bodies embedded Need to become. This is the case, for example, with a revision of the molten metal rotary kiln required for the stirring body a Leave recess in the lining and after its installation fill remaining joints with refractory potting compound.

So long the wear of the respective stirring body and the inner lining more or less in phase, let to carry out the work described above together and match up. However, it becomes problematic if, for example the stirrer is worn and needs to be replaced, however, the lining currently no renewal required. Then first the stirrer compulsorily exposed in comparison to the inner lining, before an exchange can be made and then any joints Experienced closure.

The is technically complicated montagetechnisch. Here is the invention as a whole Remedy.

Of the Invention is based on the technical problem of a molten metal rotary drum furnace develop so described in the introduction that the stirring body assembly is simplified and in particular the Rührkörperaustausch independent of wear state the inner lining can be done.

To solve this technical problem, a generic metal-melt rotary kiln is characterized in the invention in that the stirring body is formed divided and composed essentially of two detachably interconnected part bodies. -Through the DE 580 572 C Although it is already known to work with divided stirrers, but not in a molten metal rotary drum furnace, but in a rotary kiln for burning cement, lime, gypsum or similar good.

On the other hand comes the molten metal rotary drum furnace according to the invention Mostly when remelting aluminum used. In fact, it usually becomes so-called secondary aluminum melted down, in a protective bath. As is known, secondary aluminum is used to a secondary raw material, which prepares in the course of a recycling economy with the help of the described metal melting rotary drum furnaces and is melted, in a Salzbadschmelze. The Working under a salt cover allows to reduce burnup losses decrease and a big part to collect the impurities of the molten secondary aluminum in the salt.

in the Within the scope of the invention, various possibilities exist for advantageous Further education. Thus, the at least one stirring body is usually divided transversely executed. Usually there are several over the drum shell arranged arranged stirring body to particular advantage to achieve a bath movement in the molten aluminum. Basically, the Stirring, of course, too split longitudinally accomplished his and there is also a longitudinal and transverse distribution within the scope of the invention.

In the case, that the respective Rührköper transversely divided accomplished is close regularly both partial body at a common graduation level to each other. This division level extends substantially parallel to the drum shell in this Area or to the (slightly curved) Cylinder segment at the point on which the stirring body is attached. there is the distance of the aforementioned Division level to the strength adapted to the already mentioned inner lining of the furnace drum. In detail, the distance of the dividing plane from the drum shell more than 30%, in particular more than 50% and preferably more as 60% of the strength the inner lining on.

Usually is the one part body as Rührkörperbasis and the other part body as agitator blade educated. At the same time, the stirring element base is immersed in the inner lining, while the other Rührkörperschaufel protruding from it and for the necessary stirring movements in the molten bath. Because of the previously indicated position of the division level, which ultimately coincides with a top plate of the stirring body base is ensured that the headstock concerned from a certain degree of wear of the Interior lining dominates this.

For example the distance of the dividing plane from the drum shell 60% of the thickness of the inner lining, so the top plate of the stirring body is base (with removed stirring paddle) visible as soon as 40% of the inner lining worn away by wear are. Of course can other values can also be set here.

In any case wear this Circumstance the fact that an exchange of the respective stirring body due to from experience usually only then needs to be made, if in the example more as 40% of the strength the inner lining are removed. In fact, then dives the headstock the Rührköperbasis off the inner lining, so that a subsequent Rührkörperaustausch only the replacement of the stirring paddle necessary. The agitator base fitted into the inner liner leads herein, however. This allows the agitator blade to easily open the stirring body base be set, in turn, in the inner lining and / or anchored to the drum shell of the furnace drum.

To that purpose the invention at least one two part body by cross-fastening means to their common determination on the drum shell before. It likes the fastener pass through a part body and in the other part body be set. It is conceivable, for example, that the fastener in the agitator blade is anchored and a hole in the Rührkörperbasis passes through to the outside of the Oven drum to be anchored. But it can also be the other way round be moved.

Usually it is in the fastener to a fastening bolt. Depending on the weight of the stirring body or the agitator blade you become natural resort to several fasteners, evenly over the area the agitator blade are arranged distributed. Alternatively or additionally, it may be the fastener but also embedded in one of the two part body Mounting basket or a combination of mounting bolts and Act fixing basket. Regularly anchoring the mounting basket in the agitator blade, wherein the attachment basket with its protruding from the Rührkörperschaufel basket ends several holes in the Rührkörperbasis passes through and is fixed to the drum shell.

When Material for recommends the preparation of the stirring body the invention predominantly Iron, in particular gray cast iron. Of course, the stirring body via a metallic core and a cladding made of a refractory material. Combinations, for example, are just as well possible that the stirring body base made of iron, in particular gray cast iron, while the other hand Agitator blade over the metallic core, for example in the form of the mounting cage made of steel or the like and additionally the serving from the refractory material, in particular from refractory concrete, has.

in the As a result, there is provided a molten metal rotary drum furnace whose Agitator especially can be easily mounted. This is explicit not required, the inner lining in the attachment area to remove. Rather, the Rührkörperbasis remains at this point and, if necessary, connected to a renewed agitator blade, which the actual stirring movement takes over, whereas the stirring body base mainly Carrying and holding function is assigned. To the after a certain wear of the inner lining exposed dividing plane between the Rührkörperbasis and the Rührkörperschaufel or a gap present there, if necessary, against penetrating metal to protect, may be the stirring body base on its top plate with a circumferential wall and therefore in the Type of a tub running be. This is not mandatory.

It is just as well within the scope of the invention to insert spacers between the mixing-body base and the stirring-body blade as needed. As a result, the stirring body can be made adjustable within certain limits, namely in the radial direction, similar to that in the utility model DE 203 03 289 U1 already described.

in the The invention will be described below with reference to a purely exemplary embodiment drawing closer explains; show it:

1 a front view into an open Metallschmeiz rotary drum furnace according to the invention,

2a and b a longitudinal and cross-section through the molten metal rotary drum furnace in the region of a stirrer and

3a . 3b the object after 2 in another embodiment.

Shown in the figures is a molten metal rotary kiln used herein, and not by way of limitation, for reflowing aluminum Al. The aluminum Al is secondary aluminum which undergoes a melt treatment in a protective bath. In the 1 you recognize the molten zene aluminum Al, which is protected by a surface-side salt cover D from burning against a present in the burner chamber B burner.

In its basic structure, the molten metal rotary drum furnace has a rotatable kiln drum 1 , whose drum casing 2 with a plurality of stirring bodies distributed over the circumference 3 equipped. About a purely in 1 illustrated opening 4 in the oven drum 1 the burner, not shown, can be introduced into the burner chamber B, around the inside of the furnace drum 1 To remelt the aluminum Al to produce required temperatures. So that the molten aluminum Al the drum shell 2 can not attack, this is with an inner lining 5 the strength S equipped. The length L of the respective stirring body 3 is dimensioned so that the stirring body 3 opposite the inner lining 5 protrudes and generates the necessary stirring movements in the melt.

Based on the representations in the 2 and 3 it can be seen that the stirring body is designed to be divided, namely transversely divided by definition of a dividing plane T. This causes the stirring body to disintegrate 3 essentially in two parts 3a . 3b , which are detachably connected to each other and connect to each other at the common division plane T.

It is a partial body 3a as Rührkörperbasis 3a executed while the other part body 3b a stirring paddle 3b forms. It can be seen that the dividing plane T over a distance A from the drum shell 2 has, which to the already mentioned thickness S of the inner lining 5 the oven drum 1 is adjusted. In fact, the distance A is the dividing plane T from the drum shell 2 more than 30%, in particular more than 50% and preferably more than 60% of the thickness S of the inner lining 5 , That is, it applies: A> 0.3 × S ,

At the same time, the thickness S of the inner lining determines 5 also the maximum distance A of the dividing plane T from the drum shell 2 : A <S ,

In this way it is achieved that a head plate 6 the stirring body base 3a , which lies in the dividing plane T, more or less in the inner lining 5 dips. As a result, the dividing plane T or at this point necessarily existing gap between on the one hand the Rührkörperbasis 3a and on the other hand the agitator blade 3b from the inner lining 5 enclosed, so protected. This is true at least until the inner lining 5 so far worn that the dividing plane T and thus exposed the gap described. - Of course, the dividing plane T also above the inner lining 5 be arranged, if for a perfect connection of the Rührkörperschaufel 3b with the stirring body base 3a is taken care of.

Order now the two parts 3a . 3b with each other and with the drum shell 2 to connect are several, both part bodies 3a . 3b sweeping, fasteners 7 . 8th realized. In fact, the variant comes after 2 as a fastener 7 one fastening bolt each 7 for use, which in each case a bore 9 in the stirring body base 3a passes through and in the example in an internal thread 10 in the agitator blade 3b intervenes. In this way the agitator blade becomes 3b and also the stirring body base 3a on the drum shell 2 established.

In the variant after 3 there is another fastener 8th namely, a mounting basket 8th , This attachment basket 8th not only has the task, the agitator blade 3b on the drum shell 2 but at the same time acts as a metallic core 8th for a serving 11 from a refractory material, in this case from a refractory concrete. This is the metallic core 8th or attachment basket 8th made of steel, so the agitator blade 3b in this case represents a reinforced concrete part, which in the interior of the furnace drum 1 withstand prevailing conditions.

In contrast, the stirring body 3 in the variant 2 made of iron, in particular gray cast iron. Of course, both materials can be combined with each other or with other materials. So it is conceivable, according to the alternative 3 on a Rührkörperbasis 3a made of iron and not one of the refractory material with the holes located therein 9 recourse. In fact, the attachment basket passes through 8th the holes in question 9 with its basket ends 12 on the drum mantle 2 learn the desired determination.

Just as well can a Rührkörperbasis 3a from a refractory material with a stirring blade 3b made of iron or gray cast iron.

Claims (10)

Metal melting rotary drum furnace, in particular for remelting aluminum, preferably in a protective bath, with a rotatable kiln drum ( 1 ), whose drum shell ( 2 ) at least one stirring body ( 3 ), characterized in that the stirring body ( 3 ) is divided and essentially consists of two detachably interconnected partial bodies ( 3a . 3b ). A molten metal rotary drum furnace according to claim 1, characterized in that the stirring body ( 3 ) is carried out transversely. A molten metal rotary drum furnace according to claim 1 or 2, characterized in that both partial bodies ( 3a . 3b ) adjoin one another at a common dividing plane (T) whose distance (A) from the drum shell ( 2 ) to the thickness (S) of an inner lining ( 5 ) of the kiln drum ( 1 ) is adjusted. Metal-melt rotary drum furnace according to one of claims 1 to 3, characterized in that the distance (A) of the dividing plane (T) from the drum shell ( 2 ) more than 30%, in particular more than 50%, preferably more than 60% of the thickness (S) of the inner lining ( 5 ) having. A molten metal rotary drum furnace according to one of claims 1 to 4, characterized in that the one partial body ( 3a ) as a stirring body base ( 3a ) and the other part body ( 3b ) as agitator blade ( 3b ) is trained. A molten metal rotary drum furnace according to any one of claims 1 to 5, characterized in that at least one of both partial bodies ( 3a . 3b ) thorough fastening means ( 7 . 8th ) to their common definition on the drum shell ( 2 ) is provided. A molten metal rotary drum furnace according to one of claims 1 to 6, characterized in that the fastening means ( 7 . 8th ) the one partial body ( 3a ) and in the other part body ( 3b ). A molten metal rotary drum furnace according to any one of claims 1 to 7, characterized in that the fastening means ( 7 . 8th ) about a fastening bolt ( 7 ), one in the respective partial body ( 3a . 3b ) recessed mounting basket ( 8th ), or combinations thereof. A molten metal rotary drum furnace according to one of claims 1 to 8, characterized in that the stirring body ( 3 ) is made predominantly of iron, in particular gray cast iron. A molten metal rotary drum furnace according to one of claims 1 to 9, characterized in that the stirring body ( 3 ) a metallic core ( 8th ) and an envelope ( 11 ) of a refractory material.